In a medium pot add the vegetable consomme and bring to a boil. Add the diced carrot, celery root, and leeks. Cook for 2 to 3 minutes and add the grated horseradish. Let the consomme simmer for 15 minutes.

Next add the tenderloin, cover the pot and cook until the desired temperature. Approximately 9 minutes for medium. Remove the tenderloin and allow to rest for at least 10 minutes. Meanwhile, strain the consomme and continue to reduce over high heat.

When ready to serve, add the creme fraiche, season with salt and pepper, and incorporate the 2 ounces of the butter. The sauce should coat the back of a spoon. To present the dish, slice the tenderloin, and serve with the reduced sauce